The present invention relates generally to motorized transportation vehicles, and more specifically to a craft having the ability to interchangeably convert between an aircraft configuration and an automobile configuration. The craft includes numerous novel features relating to the practicality and safety of such a vehicle, such as secure stowage of all flight surfaces and avionics sensors during ground operations, the use of separate, discreet power plants for ground and flight operations and other novel features.
The idea of a vehicle, which is capable of both flight operation and highway operation, has been a dream since shortly after the development of the first powered aircraft in the early part of the twentieth century. Numerous inventors have attempted to produce such a combination craft, generally known as a flying car or roadable aircraft. Some of these attempts have met with limited success, in two cases the machines have been type certified by the Civil Aeronautics Agency (now the Federal Aviation Administration) as production aircraft. However, none of these craft have been commercially successful or particularly practical. The design requirements of a ground vehicle are entirely different to those of an airplane and the result of trying to marry the two together into one craft has hitherto been to produce a vehicle which is impractical in either environment.
In order to afford true practicality and safety, all flight surfaces and avionics sensors must be securely stowed within the body of the vehicle during ground operations, so that these essential and delicate components are protected from damage or tampering. The craft must also have a body size and shape that allows it to be operated conveniently as an automobile; to fit within a regular parking space and a single car garage.
In order to satisfy both of these requirements, flight surfaces must be articulated in such a way as to occupy a relatively small space during ground operations and yet also be capable of being securely deployed in their extended position during flight operations. One design, Pat. No. 4,269,374xe2x80x94Miller, has flight surfaces that all fold within the body, however the method of folding and the choice of conventional empennage design result in an aircraft with insufficient wing area and an impractical shape for operation as an automobile.
Another overriding limitation on the practicality of such a craft lies in the limitations and requirements of the power plant. The power requirements of a ground vehicle and an aircraft are entirely different. Not only does an aircraft require generally more power than does a ground vehicle but the steady, sustained, thrust required of an aircraft is entirely different to the wide torque range and fast response required of a ground vehicle. Previous inventions have generally relied on a single power source, a gasoline engine, with some kind of transmission linkage to drive either a propeller for flight operations or the vehicle wheels for ground operations. This arrangement, while appearing attractive, actually carries a severe weight penalty and does not supply the type or amount of power required for both operating modes.
A discussion of the related art of which the present inventor is aware, and its differences and distinctions from the present invention, is provided below.
U.S. Pat. No. 2,713,465 issued on Jul. 19, 1955 to Harry E. Novinger describes a Combined Air-Ground Vehicle having an airfoil shaped forward fuselage or body and an upwardly and rearwardly disposed wing, resulting in a negative stagger biplane configuration. Large side members serving as end or tip plates for the relatively low aspect ratio fuselage and wing connect the fuselage and rearward wing. The flight components cannot be folded or stowed for ground operations, unlike the present road/air vehicle. The craft utilizes a single gasoline engine for both ground and flight operations. Novinger""s short span, low aspect ratio upper wing and fuselage provide for relatively poor flight ability. The tricycle wheel arrangement of the Novinger machine is unlike the more stable rectangular pattern of the wheels of the present road/air vehicle.
U.S. Pat. No. 2,767,939 issued on Oct. 23, 1956 to Moulton B. Taylor describes a Flying Automotive Vehicle Assembly, comprising a left and right wing structure, tail cone structure, and empennage, all of which are separable from a central automobile or cabin structure. The wings fold rearwardly against the tail cone of the assembly, which is removed from the automobile or cabin structure and towed behind for road use. The flight components cannot be folded or stowed for ground operations, unlike the present roadable aircraft. The craft utilizes a single gasoline engine for both ground and flight operations. This is one of only two road/air vehicle or flying car designs ever certified for production by the CAA or FAA.
U.S. Pat. No. 2,940,688 issued on Jun. 14, 1960 to Edward F. Bland describes a Roadable Aircraft And Sailboat having a lifting body configuration somewhat in the manner of the fuselage shape of the Novinger craft discussed further above. However, the rear fuselage includes a central channel before the rear propeller, somewhat in the manner of one nacelle or channel of the twin engine Custer Channel Wing aircraft developed in the 1950s. The Bland craft also includes folding wings, which may be folded with their spans rearwardly atop the fuselage for road use, or which may be extended vertically to serve as sails. The flight components cannot be folded or stowed for ground or water operations. The craft utilizes two engines, one for road and water use and the other for airborne use. However, the two engines are of similar design and may be linked together to provide the required power for takeoff and climb when used as an aircraft. This arrangement is unlike the two-engine configuration of the present road/air vehicle, which utilizes entirely different types of engines for ground and flight operations.
U.S. Pat. No. 3,012,737 issued on Dec. 12, 1961 to David R. Dodd describes a Combination Land And Air Vehicle having a twin boom tail assembly and folding wings. The wings fold in a spanwise direction as well as at the roots, with the leading portion folding forwardly and horizontally next to the fuselage, and the rearward portion folding downwardly to form an essentially vertical surface parallel to the fuselage sides when folded. The wings remain external during ground operations. The tail assembly does not fold. The flight components cannot be folded or stowed for ground operations, unlike the present road/air vehicle. The craft utilizes a single gasoline engine for both ground and flight operations. The tricycle wheel configuration is unlike the square wheel configuration of the present craft.
U.S. Pat. No. 3,371,886 issued on Mar. 5, 1968 to Robert O. Schertz describes an Aircraft Adapted For Highway Usage, having a rearwardly disposed main wing, a forwardly disposed canard surface and a four-wheel configuration as in the current invention. However, Schertz uses large vertical stabilizers at the roots of the main wing, rather than the smaller lighter fins at the wing tips of the current invention. No provision is made for secure stowage of the wings, which remain external during ground operation and only one engine is utilized for both ground and flight operations.
U.S. Pat. No. 4,269,374 issued on May 26, 1981 to Harvey R. Miller describes a Combined Road Vehicle And Aircraft, in which the wings, tail assembly and propeller drive all fold into the structure of the body or cabin portion for carriage during road use. However, the craft is of a conventional, tailplane empennage, configuration and the wings rotate and fold parallel to the body, similarly to the folding configuration of the Dodd craft discussed further above. The lack of intermediate folding for the wings, resulting in a short span craft, as well as the conventional wing configuration result in a craft unlike that of the present invention. The craft utilizes a single gasoline engine for both ground and flight operations.
U.S. Pat. No. 4,627,585 issued on Dec. 9, 1986 to Harry Einstein describes a pusher type aircraft of conventional tail empennage design. For ground operations the main wing is folded spanwise at the wing root and at about ⅔rds span so that the wings fold to the center and lay one on top of another. Also the tail empennage is extended forwards on a sliding boom for ground operations, effectively reducing the length of the vehicle. The landing gear is of a tricycle type. A pusher type propeller is driven by an aviation engine located within the fuselage and the design does utilize an independent engine, also located within the fuselage, to drive the wheels for land use. The flight components cannot be securely stowed inside the body of the craft for ground operations.
U.S. Pat. No. 4,579,297 issued on Apr. 1, 1986 to Joseph N. Ayoola describes an Air, Land and Sea vehicle of conventional, tailplane empennage configuration. The craft utilizes four wheels that move outwardly for highway use, and inwardly into stored position for flight and water use. The flight surfaces do store within enclosed compartments for water and flight use, however the empennage surfaces slid into slots at the rear of the craft and the main wing folds from the wing root as well as telescoping. The craft utilizes separate propulsion systems for the water and flight modes, however there is only aerodynamic propulsion for ground use.
U.S. Pat. No. 4,881,701 issued on Nov. 21, 1989 to Gary M. Bullard describes a Combination Automobile And Airplane having a two place tandem, pusher engine, canard configuration, somewhat like the configuration of the Vari-Eze and Long-Eze aircraft designs of Burt Rutan. However, the canard wings do not fold and the main wings fold externally to the craft. The craft uses a propeller for flight operations which is disengaged for road use. The craft has no secure stowage of the wings and does not utilize discreet power plants, as is in the current road/air vehicle.
U.S. Pat. No. 5,050,817 issued on Sep. 24, 1991 to Harvey R. Miller describes a Combined Road And Aircraft Vehicle of a similar configuration to the vehicle of the U.S. Pat. No. 4,269,374 to the same inventor, discussed further above. The primary difference is that the vehicle of the ""817 Patent stores the wings along the sides of the road vehicle, rather than in storage compartments in the sides of the road vehicle, as in the ""374 Patent. Other features, e. g., tail folding, are similar between the two Miller patents, and are unlike the means used in the present invention.
U.S. Pat. No. 5,435,502 issued on Jul. 25, 1995 to Kenneth G. Wernicke describes a Flying And Road Vehicle of a configuration similar to that of the ""465 U.S. Patent to Novinger discussed further above, i. e., having a relatively low aspect ratio wing to meet maximum road width requirements without folding. None of the Wernicke flight components can be folded or stowed for ground operations, unlike the present road/air vehicle. The craft utilizes a single gasoline engine for both ground and flight operations.
U.S. Pat. No. 5,984,228 issued to Roger Pham on Nov. 16, 1999 describes a three surface aircraft with a one-piece main wing rotatably mounted on top of the fuselage. The aircraft""s wing is enlargeable with additional wing tip segments. Propulsion is by a ducted fan in flight mode and a hydraulically driven rear wheel in ground mode. The flight components cannot be stowed for ground operations, unlike the present roadable aircraft. The craft utilizes a single gasoline engine for both ground and flight operations.
U.S. Pat. No. 6,224,012 issued to Donald H. Wooley on May 1, 2001 describes a Roadable aircraft with a single power source to propel the vehicle in flight and on the ground through aerodynamic thrust. The craft is a canard configuration with a main wing, which swivels 90xc2x0 for ground operations. The canard does not fold. The flight components cannot be stowed for ground operations, as in the present roadable aircraft. The craft utilizes a single gasoline engine for both ground and flight operations and has a tricycle type wheel arrangement.
An aircraft design presented by Labiche Aerospace at http://www.labicheaerospace.com describes a craft with the look of a sports car but with three flight surfaces, which unfold for flight operations. The present inventor does not know of any patent filed on this craft. The labiche design differs from the present invention in its use of three flight surfaces, the folding a swinging action of the main wing, the lack of secure stowage of the rear flight components and the use of a single gasoline engine for both ground and flight operations.
Finally, a publication titled Roadable Aircraftxe2x80x94From Wheels To Wings, by Palmer Stiles, copyright 1994 and published by Custom Creativity, Inc., Melbourne, Fla., includes a comprehensive, but not exhaustive, collection of at least portions of U.S. Utility and Design Patents issued for road/air vehicle and flying automobiles. None of the patents published in the book, but not discussed in detail further above, are felt to be more closely related to the present invention than those discussed herein.
None of the above inventions and patents, either singly or in combination, is seen to describe the instant invention as claimed.
The following prior art reflects the state of the art of which applicant is aware and is included herewith to discharge applicant""s acknowledged duty to disclose relevant prior art. It is stipulated, however, that none of these references teach singly nor render obvious when considered in any conceivable combination the nexus of the instant invention as disclosed in greater detail hereinafter and as particularly claimed.
The other prior art listed above but not specifically described further catalog the prior art of which the applicant is aware. These references diverge even more starkly from the references specifically distinguished above.
The present invention comprises a road/air vehicle, which may be reversibly changed from an aircraft configuration to an automobile configuration. The aircraft configuration comprises two flying surfaces, with a generally centrally and rearwardly located main wing, having two vertical fins at the tips providing directional stability and rudder control, plus a smaller forward surface serving as a canard stabilizer and providing pitch control.
Conversion from flight to ground mode is accomplished in the following way: Four doors are opened in the body, a door in the forward upper portion of the body, a door in the upper center section of the body and a door in the each of the left and corresponding right center sides of the body. The left and corresponding right canard wings swing approximately 180xc2x0 from their wing roots to rest within the extent of the body, one resting above the other. Concurrently the left and corresponding right main wings, divided into four section, are folded spanwise between each section in alternating opposing directions. The first section, not a flying surface but a connecting arm remaining at all times within the body craft, beginning at a point adjacent to the center of the craft and running to the wing root, swings downwards approximately 90xc2x0. The second section, lateral to the first, starting at the wing root and running to a point approximately ⅓ of the span, swings upwards approximately 180xc2x0. The third second, lateral to the second section, running from the extent of the second section to a point approximately ⅔ of the span, swings downwards approximately 180xc2x0. The fourth section, lateral to the third, running from the extent of the third section to the wing tip, swings upwards approximately 180xc2x0. In this way the wing sections folded positions are adjacent and parallel to each other, one laying against the other, and approximately vertical. The left and corresponding right center most hinge points are displaced vertically so that the wing tips, which are approximately horizontal in their folded positions, rest one above the other. Finally the four doors described above are closed, enclosing the folded wings within the body. Locking means at each of the hinge points secure the wings in their unfolded and folded positions. Locking means also secure the doors.
The present road/air vehicle uses a laterally symmetrical rectangular wheel or landing gear configuration, which is retractable into enclosed compartments for flight operations. A gasoline engine through an automatic transmission for ground operations drives two of the wheels. Two forwardly disposed wheels are steerable for ground operations.
The motive power system comprises a gasoline engine/transmission unit mounted in the center/front section of the body driving the front or rear wheels for ground operations and a jet thrust powerplant mounted in the rearward section of the body to provide forward thrust for flight operations.
Accordingly it is a principal object of the invention to provide an improved road/air vehicle having jet thrust power for flight operations and discreet torque power for ground operations. It is another object of the invention to provide an improved road/air vehicle having two symmetrically lateral flight surfaces, comprising a canard wing plus a main wing with tip fin stabilizers. It is another object of the invention to provide an improved road/air vehicle including multiply folding flight components, which components remain attached to the structure and are securely stowed within the body of the craft for ground operations. It is a further object of the invention to provide an improved road/air vehicle that discrete power supplies for the two available modes. With a jet engine providing forward thrust for air operations and an suitable engine/transmission unit providing direct drive to the crafts wheels for ground operations.
It is a further object of the invention to provide an improved road/air vehicle having a rectangular, laterally symmetrical, retractable undercarriage configuration comprising two rearwardly disposed wheels and two, steerable, forwardly disposed wheels for ground operation.
It is a further object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which are, dependable and fully effective in accomplishing its intended purposes.